What characterizes P-wave arrivals on the far side of the Earth at epicentral angles beyond 140°?
A) They are slowed by about 40% due to refraction through the outer core.
B) The waveforms of their signals are all upside down due to coming out the other side of the Earth.
C) They are amplified in intensity by the Ni- Fe in the core.
D) They arrive sooner than expected because of the abrupt increase in velocity at the mantle- core boundary.

Question

Quizplus · Accepted Answer

P-waves are slowed by about 40% due to refraction through the outer core, which is less dense than the mantle, causing a decrease in velocity.

What Characterizes P-Wave Arrivals on the Far Side of the Earth